Comment by jjk166 | Hacker News Reader

Comment by jjk166 | Hacker News Reader

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If you personally are a direct descendant of Abraham, or any other specific individual who lived approximately 3000 years ago, statistically you do not carry any DNA from that ancestor. While there are some nuances relating to differences in how the different sexes pass on their genes, as a rough approximation you carry half the base pairs of each of your parents, who each carry roughly half from their parents, and so on. So you carry 1/2^n base pairs from an individual n generations before you. The human genome is 3 billion base pairs, meaning in 31 generations the odds of having a single base pair from a specific ancestor is about 50%. 3000 years is about 120 generations, so your odds of having a basepair from a specific ancestor that far back are about 1 in 1,000,000,000,000,000,000,000,000,000. The only exceptions that matter on that timescale are the y-chromosome along the male-only line descent and the mitochondrial DNA along the female-only line of descent.

So by that logic nobody has any DNA in common with neanderthals, right? Try again. You’re missing a big, big, gotcha.

Aside, Jewish line is determined by matrilineal descent. By your own logic the mitochondrial DNA is shared, which is a rather significant aspect to simply gloss over.

No one has any DNA that can be traced to a specific Neanderthal, no.

Of course people have DNA in common with their ancestors as a group, hell we share a lot in common with fish. But it's because these genes are common that they enter and re-enter your family tree at multiple points.

And your mitochondrial DNA definitely doesn't descend from Abraham, a male incapable of passing on mitochondrial DNA, so there's a reason I gloss over female line descent.

Your pseudoscience above would make it seem nobody has any DNA from any ancestors at all, as there were not your 10^Whatever creatures ever in existence. Once you figure out the bug in your logic there, you will perhaps see the failure of the rest of your argument. Hint: inbreeding.

It's actually called pedigree collapse, but it doesn't really change anything - the fact that the same ancestor may appear in multiple places in your family tree makes it harder to trace a gene back along any given line, not easier. You undoubtedly share an enormous amount of genetic similarity with Abraham, it's how you got it that is forever scrambled.

It nullifies your entire diatribe and all of its bogus numerics, but O.K.

Good sign of someone arguing dishonestly is that when you call out their lies, they tell you that the truth doesn’t matter.

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